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LDmicro Forum - PIC 16F887

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having a problem with 16f887 if i have contacts IN and RB4 set as a coil out on a rung by itself its always high out
but if i parallel it in another rung with other coils its then low like it is supposed to be any ideas?
Fri Apr 7 2023, 09:56:10
(no subject) (by JOHN DEVITO)
p.s it works in simulator but when i program pic it doesnt work RB4 is always high
Fri Apr 7 2023, 11:22:59
(no subject) (by Boris)
check datasheet some RB have weak pull up use them as input and use like RA5 pin as out
Fri Apr 7 2023, 15:15:28
(no subject) (by JOHN DEVITO)
is there a way with LDMICRO to disable the pullups?
Fri Apr 7 2023, 15:25:25
(no subject) (by john)
it seems to be with RB0 RB1 RB2 RB3 if any of these are used as inputs it messes with RB4 RB5 RB6 RB7 outputs
Fri Apr 7 2023, 23:21:23
(no subject) (by MGP)
You can do that by changing bits in the Option register and WPUB register, see example.

In the Option register they are all affected and in the WPUB register individually.
Sat Apr 8 2023, 02:40:20, download attachment 16F887_WPU.ld
(no subject) (by john)
thanx MGP but that is a little advanced for me which is why i use LDMICRO otherwise id just write and program normal
Sat Apr 8 2023, 10:28:09
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